AMONG HYENAS, FEMALES DOMINATE JITTERY MALES

It was hours before dawn when the wailing and howling of nearby hyenas brought human sleep to a premature end. As the African sky lightened, the cause for the commotion among these carnivores of undeserved ill repute became obvious.

During the night, the hyenas had captured and devoured a wildebeest, a cattle-sized herbivore that is their most frequent meal. By daybreak, all that was left of the unfortunate prey were horns and hoofs. As the sun rose, two jackals and a dozen vultures moved in to pick up scattered scraps of meat as the hyenas wandered off, replete - but some of them, notably the dominant females, more replete than others.

Laurence Frank, the graduate student in zoology whose ''study animals'' made the kill, is here because of his interest in the social interactions of the female-dominated spotted hyena clan (other species, the brown and striped hyenas for example, have male-dominated arrangements). Mr. Frank, who is pursuing his Ph.D. degree at the University of California at Berkeley, believes his research will ultimately help to sort out such important human questions as the basic differences between male and female behavior and the effects of hormones on behavior.

Outside his tent home on the edge of this dry-season habitat for millions of Africa's wild animals, Mr. Frank explained that the spotted hyena ''has achieved the ultimate in role reversal and has lived this way for millions of years. The hyena is a natural model to study such questions as the brain differences between males and females and the role that testosterone plays in aggression.''

So complete is female dominance among spotted hyenas that even an adult high-ranking male is nervous around a pubescent female, Mr. Frank has observed. He has also seen an adult male retreat when approached by the tiny cub of a dominant female. ''But the best expression of dominance is who gets to eat when the food supply is limited,'' Mr. Frank said. Though he suspects males, who are usually hungry, do most of the killing, females quickly take over the meal and force the males to wait until they and their cubs are done feeding. By the time the males get their turn at the table, there is often little or nothing left to eat.

The dominant female and her cubs eat first, and Mr. Frank found that the cubs of high-ranking females get to eat at kills at a much younger age than other cubs do. He has also discovered that dominance seems to be inherited - passed on from the dominant mother to her daughters and granddaughters. Apparently no fighting is needed to establish rank, he said. Hyenas repeatedly remind clanmates of their status through a ''greeting ceremony'' in which two animals sniff each other's hindquarters. The subordinate animal starts by raising a leg to expose the erect genitalia.

The one exception he has seen to total female dominance was the son of the dominant female, who was allowed to eat with the females. He was also tolerated in the clan for two years longer than other males, who are generally forced out by the age of 2. The Sexes Look Alike

To the untrained eye, females look exactly like males, which gave rise long ago to the myth that hyenas are hermaphrodites. The female genitalia are greatly enlarged and mimic in appearance and erectile capacity the genitalia of the male.

It took Mr. Frank months of observation of the resident 50-member clan here before he could quickly tell males from females. The females, he found, are larger and fatter (because they eat more) and their sham scrotum is filled with fat, not testes, giving them a somewhat different shape. He also uses behavioral clues - ''the males are so nervous around females that I now can easily tell which is which.''

To distinguish one hyena from another, he took thousands of pictures, learned the unique spot patterns of each animal and then gave each a name. It was more than a year before he could readily identify every hyena in the clan, and each year he has to get to know a new crop of cubs.

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Since hyenas are generally inactive by day, most of Mr. Frank's studies are done at night and in the dim light of dawn and dusk. International Telephone and Telegraph lent him a huge pair of battery-powered goggles, a military device that permits humans to see in the dark.

In addition, some of his study animals have been marked with ear notches and others are fitted with radio transmitters so that he can keep better track of their wanderings. His research has been supported by National Geographic, the National Science Foundation and Earthwatch, a nonprofit organization that sponsors field research.

He has also temporarily tranquilized animals to obtain blood samples. Working with Julian Davidson, a physiologist at Stanford, Mr. Frank has found that testosterone levels and dominance are closely related; the most dominant female has a testosterone level as high as some males. It is six times that of the average female and five times that of the female next in line.

''The big question is why in the course of evolution the males permitted themselves to be so totally eclipsed by the females. Why do they tolerate this total subservience, this wretched existence as outcasts who are hungry all the time?''

Mr. Frank believes the answer lies in part in the relatively poor reproductive performance of the spotted hyena. Hyenas reproduce much more slowly than other social carnivores, such as lions and wolves. They have no particular breeding season and usually give birth to two cubs every year or two. Though the mother carefully tends the infant cubs and keeps them in and around an underground communal den, one of her cubs often dies a few months after birth.

The reasons for cub mortality are not fully understood, though some cubs are known to fall prey to lions and others may succumb to starvation when the food supply dwindles and the mother is forced to leave the den on an extended hunt. The hyena cub's long period of dependence - about two years - also works against its chances of survival. Once weaned, the cubs must fend for themselves since their mothers bring back no food for them. ''Weaning tantrums'' are common among hungry cubs abruptly separated from the breast.

Mr. Frank suggests the following evolutionary scenario: Originally, like the brown hyena and the striped hyena, the spotted hyena was once a male-dominated scavenger, its numbers limited by a meager food supply. Through the millenia, the spotted hyena discovered that by hunting cooperatively it could kill large animals. This increased the food supply and permitted a population explosion. Now large numbers of animals would be trying to feed at a kill, with the cubs getting last licks and often starving.

Unlike the reproductively more successful lions and wolves, this situation would have created ''a tremendous selective pressure to increase cub survival,'' Mr. Frank said. ''A female who was tough could better defend her cubs. One route to female dominance is to increase the level of testosterone, which goes hand in hand with aggressive behavior and larger body size.'' The females with increased testosterone would be more successful at raising young and thus more likely to pass on their high-testosterone genes to the next generation.

Mr. Frank's next field studies will be of mating behavior, a highly secretive event in hyena life. He conceded that ''in four years, I've seen only three matings. I want to know who mates with whom and how it relates to dominance and reproductive success.'' Back in California, Mr. Frank would like to establish a colony of young hyenas to study more closely the influence of testosterone on behavior. Other studies would seek to determine where the female's testosterone comes from and what effect it has on her brain development. Jane E. Brody

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A version of this article appears in print on August 31, 1982, on Page C00001 of the National edition with the headline: AMONG HYENAS, FEMALES DOMINATE JITTERY MALES. Order Reprints|Today's Paper|Subscribe